A current-driven magnetization reversal using the spin-transfer effect in a micromagnet has been proposed as a method for writing in a magnetic memory, and products in which data is written using the spin-transfer effect have been developed. Similarly, it is proposed to apply a spin-torque oscillator realizing magnetization precession at several gigahertz to tens of gigahertz by using the spin-transfer effect to a reading and writing head in a next-generation large-capacity hard disk drive (HDD), and to communication technology.
As an example of application to the HDD reading and writing head, there is a recording method, which reduces the necessary writing field by injecting energy into the recording medium through ferromagnetic resonance induced by the high-frequency magnetic field generated by a spin-torque oscillator.